The number of atoms or formula units in "x" grams of an element or molecule where "x" is the atomic or molecular mass. (Always equal to 6.02 x 10^23)

Mole

6.02x10^23 items, can be anything. The number of atoms in one mole (atomic mass in grams) of a monoatomic element. The number of formula units in one mole (formula mass in grams) of an ionic compound. The number of molecules in one mole (formula mass in grams) of a molecular substance)

For any substance, write a general formula to convert from Moles to Grams

g=(n)(MM) where, n = moles MM = molecular mass g = grams

For any substance, write a general formula to convert from Grams to Moles

n = g/MM; n = moles; MM = molecular mass; g = grams

For any substance, write a general formula to convert from Moles to Number of Particles

(n)(6.02x10^23) = P; n = number of moles; P = number of particles

For any substance, write a general formula to convert from Number of Particles to Moles

n = P/6.02x1023; n = number of moles; P = number of particles

Reactants; Products

1) The starting materials in a chemical reaction; 2) The substances formed in a chemical reaction

Balance Equations: H2 + N2 ↔ NH3; NaCL + Br2 ↔ NaBr + Cl2

1) 3H2 + N2 ↔2NH3; 2) 2NaCl + Br2 ↔2NaBr + Cl2

Diatomic; list 7 diatomic elements found in nature

A molecule composed of two atoms. H2, N2, O2, Cl2, F2, Br2, F2, I2

Synthesis or combination

A reaction where 2 or more elements form a compound; N2 + 3H2 ↔2NH3; 2H2 + O2 ↔ 2H2O

The distribution of electrons into shells and sublevels for an atom of an element. Each element has a unique electron configuration.

Write the electron configuration for 1) Lithium; 2) Iron

1) 1s2, 2s1; 2) 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d6

Valence

The number of electrons in the atom's highest numbered shell.

What are the valences of the elements of families IA through VIIIA?

The valences of elements in groups IA - VIIIA are the element's column number. For example, the valence of Na is 1; O is 6

Electronegativity difference

A number found by taking the difference between the electronegativities of two atoms in a bond. Its value determines the type of bond.

Describe an ionic bond in terms of electronegativity difference

When the EN values differ by 1.7 or more. The atom with higher EN borrows the electrons from the atom with lower EN. The resulting positive and negative ions attract.

Nonpolar covalent bond

when the EN difference is very small (less than 0.5). Two bonded atoms share the valence e-. The resulting molecule has no electrostatic charge.

Polar covalent bond

When the EN difference is between 0.5 and 1.7, the bonding electrons stay closer to the more electronegative atom. Electrons are shared unequally.

Coordinate covalent bond

When both electrons in a covalent bond are supplied by one atom

Metallic Bonds

A sea of electrons surrounding positive metal ions

Hydrogen bonding

Formed when hydrogen is bonded to oxygen, fluorine, or nitrogen. The hydrogen of one molecule becomes attracted to the electronegative element of the other molecule. These intermolecular attractions cause higher boiling points than predicted

Octet Rule

Atoms tend to gain or lose outer shell electrons in order to achieve a noble gas configuration of 8 electrons

Double and Triple covalent bond

In a double bond, wo pairs of electrons are shared. In a triple bond, three pairs of electrons are shared.

Resonance structures

Where there is more than one possible bonding structure in a molecule

Hybrid orbitals (list three types)

Where 2 or more pure atomic orbitals are mixed to form identical hybrid orbitals (ex. Sp, sp2, sp3)

Describe hybrid bonding in water, ammonia, methane

sp3 bonding results in a tetrahedron shape with bond angles of 109.5˚ in methane and slightly less in water and ammonia.

Sigma bonds & Pi bonds

A sigma bond is present between any 2 orbitals except when 2 p orbitals share electrons; then this is a pi bond